Precision study of B^* B\pi coupling for the static heavy-light meson

TL;DR

This paper presents a high-precision lattice QCD calculation of the B^*B extpi coupling using all-to-all propagators and low-mode averaging, demonstrating improved signal quality and efficiency for unquenched simulations.

Contribution

It introduces an effective method employing all-to-all propagators with low-mode averaging to accurately compute the B^*B extpi coupling in static heavy-light mesons.

Findings

Low-mode averaging enhances signal quality significantly.

All-to-all propagators are efficient for high-precision calculations.

Method is promising for unquenched QCD studies.

Abstract

We compute the B^*B\pi coupling \hat{g}_{\infty} for static heavy-light meson using all-to-all propagators. It is shown that low-mode averaging with 100 low-lying eigenmodes indeed improves the signal for the 2-point and 3-point functions for heavy-light meson significantly. Our study suggests that the all-to-all propagator will be a very efficient method for high precision computation of the B^*B\pi coupling especially in unquenched QCD where the number of configurations is limited.